Background and objectives: Breastfeeding promotion is an important public health strategy for counter-balancing the negative effects of maternal overweight and obesity. Colostrum contains melatonin, which can attenuate the impacts of excessive maternal weight and boost the infant’s immune system. Therefore, the objective of this study was to analyze the effects of melatonin on mononuclear (MN) phagocytes from the colostrum of women with pre-gestational obesity. Materials and Methods: Colostrum samples were collected postpartum from 100 women at a public hospital in São Paulo, Brazil. The donors were divided into two groups: the control group and the high body mass index (BMI) group. Melatonin levels in the colostrum were determined by an ELISA Kit, and the functional activity of MN cells was assessed using the phagocytosis assay by flow cytometry, and reactive oxygen species (ROS), intracellular calcium, and apoptosis were assessed by fluorimetry using a microplate reader. Results: The colostrum of mothers with pre-gestational high BMI exhibited higher melatonin levels (p < 0.05) and lower phagocytosis (p < 0.05) and ROS release (p < 0.05). Superoxide release was similar between the normal and high BMI groups (p > 0.05). Intracellular calcium release and apoptosis were also higher in the high BMI group (p < 0.05). Melatonin levels likely increased the phagocytosis rate and reduced intracellular calcium release and the apoptosis index (p < 0.05). Conclusions: The results suggest that melatonin is a possible mechanism for maternal–infant protection against obesity and restores the functional activity of colostrum phagocytes in obese mothers.

Amazonas suffered greatly during the COVID-19 pandemic. The mortality and fatality rates soared and scarcity of oxygen and healthcare supplies led the health system and funerary services to collapse. Thus, we analyzed the trends of incidence, mortality, and lethality indicators of COVID-19 and the dynamics of their main determinants in the state of Amazonas from March 2020 to June 2021. This is a time-series ecological study. We calculated the lethality, mortality, and incidence rates with official and public data from the Health Department. We used the Prais–Winsten regression and trends were classified as stationary, increasing, or decreasing. The effective reproduction number (Rt) was also estimated. Differences were considered significant when p < 0.05. We extracted 396,772 cases of and 13,420 deaths from COVID-19; 66% of deaths were in people aged over 60; 57% were men. Cardiovascular diseases were the most common comorbidity (28.84%), followed by diabetes (25.35%). Rural areas reported 53% of the total cases and 31% of the total deaths. The impact of COVID-19 in the Amazon is not limited to the direct effects of the pandemic itself; it may present characteristics of a syndemic due to the interaction of COVID-19 with pre-existing illnesses, endemic diseases, and social vulnerabilities.

Adiponectin and leptin play roles in the hunger response, and they can induce the inflammatory process as the initial mechanism of the innate immune response. It is possible for alterations in the levels of these adipokines to compromise the functional activity of human colostrum phagocytes. Therefore, the objective of this study is to analyze the effects of adiponectin and leptin on colostrum mononuclear (MN) cells. Colostrum was collected from 80 healthy donors, who were divided into two groups: the control group and the high body mass index (BMI) group. MN cells were used to analyze phagocytosis by flow cytometry, and reactive oxygen species (ROS), intracellular calcium, and apoptosis were assessed by fluorimetry using a microplate reader. Adipokines restored the levels of phagocytosis to the high BMI group (p < 0.05), with a mechanism that is action-dependent on the release of ROS and intracellular calcium. However, adiponectin and leptin simultaneously contributed to better microbicidal activity, thus reflecting an increase in the apoptosis level (p < 0.05) in the high BMI group. Probably, the maintenance of the balance between adiponectin and leptin levels enhances the protection and decreases the indices of neonatal infection in the breastfeeding infants of women with high BMI values. Therefore, policies that support pre-gestational weight control should be encouraged.

Pregnancy complicated by obesity is associated with adverse triggered gestational and neonatal outcomes, with reductions in the subtypes of CD4+ T-lymphocytes representing the modulators of inflammation. It needs to be better established how maternal nutritional statuses impact the neuroendocrine–immune system’s action and affect the immunological mechanisms of the maternal–infant relationship via breastfeeding. This study examined the effects of maternal obesity on human colostrum lymphocytes and the intracellular mechanisms of lymphocyte modulation in the presence of leptin, adiponectin, and melatonin via cell proliferation; the release of intracellular calcium; and apoptosis induction. This cross-sectional study analyzed colostrum samples from 52 puerperal splits and divided them into overweight and eutrophic groups. Colostrum lymphocytes underwent immunophenotyping and cell proliferation by flow cytometry and intracellular calcium release and apoptosis assays by immunofluorescence in the presence or absence of hormones. Significant differences were considered when p < 0.05 by the chi-square or t-test. Maternal obesity reduced the population of T-lymphocytes and TCD4+ in human colostrum and proliferative activities (p < 0.05). These hormones restore lymphocyte proliferation to a level similar to the eutrophic group (p < 0.05). Leptin, adiponectin, melatonin hormones, and biological actions consolidated in the scientific literature also represent maternal and infant protection mechanisms via colostrum and the modulation of human colostrum lymphocytes.

Human colostrum and milk contain diverse cells and soluble components that have the potential to act against tumors. In breast cancer, macrophages play a significant role in immune infiltration and contribute to the progression and spread of tumors. However, studies suggest that these cells can be reprogrammed to act as an antitumor immune response. This study aimed to evaluate the levels of melatonin and its receptors, MT₁ (melatonin receptor 1) and MT₂ (melatonin receptor 2), in colostrum and assess the differentiation and polarization of the colostrum macrophages modulated by melatonin in the presence of breast tumor cells. Colostrum samples were collected from 116 mothers and tested for their melatonin and receptor levels. The colostrum cells were treated with or without melatonin and then cultured for 24 h in the presence or absence of breast tumor cells. The results showed that melatonin treatment increased the expression of MT₁ and MT₂ in the colostrum cells. Furthermore, melatonin treatment increased the percentage of M1 macrophages and decreased the percentage of M2 macrophages. When the colostrum macrophages were cocultured with breast tumor cells, melatonin reduced the percentage of both macrophage phenotypes and the cytokines tumor necrosis factor-alpha (TNF-α) and interleukin 8 (IL-8). These data suggest that melatonin can regulate the inflammatory process via M1 macrophages in the tumor microenvironment and, simultaneously, the progression of M2 macrophages that favor tumorigenesis.

Background: High blood pressure is an important public health problem due to its high prevalence, the difficulty to control it, and its high contribution to morbidity. A series of changes may be linked to the aging process, compromising cardiac conduction, and reducing cardiovascular baroreceptor function. Advancing age promotes a decline in heart rate variability and this decrease can increase the probability of cardiovascular disease. The aim of this study was to analyze the autonomic modulation of heart rate in hypertensive elderly individuals during and after a session of aerobic exercise, and to compare it with elderly individuals without cardiovascular or metabolic disease. Our study was a non-randomized controlled study with hypertensive elderly (HBP group) and elderly without cardiovascular and/or metabolic diseases (control group). Data on blood pressure and heart rate variability (HRV) were collected before, during, and after 30 min of aerobic physical exercise on a treadmill. There was a reduction in HF (ms²) and SD1 (ms) in the 5 min of recovery for the elderly in the control group. The elderly in the control group also had greater RMSSD and SD1 30 min post-exercise when compared to the initial mins of recovery. We concluded that there was no difference in autonomic modulation and global heart rate variability between elderly individuals without cardiovascular and metabolic diseases and hypertensive individuals after a bout of aerobic exercise. Elderly individuals without metabolic diseases showed a decrease in parasympathetic modulation and global variability between the time of rest and 5 min of recovery. However, up to 30 min of post-exercise recovery, they restored parasympathetic activity.